Account of Experiments

The pressure of loose earth against revetment walls is a subject which is frequently being brought in a practical manner under the notice of engineers. A considerable number of theoretical investigations have been published by Coulomb, Rankine, Lévy, Boussinesq, and others, on this subject, but it appears that there is a singular deficiency of experimental data for testing the accuracy of the results of theory. The following Paper contains an account of some experiments made with that view in the summer of 1877. Circumstances prevented the Author from carrying out his original intention of experimenting with various forms of apparatus and various materials. Although, then, the investigation is somewhat incomplete, yet it seemed to have been carried far enough to establish several propositions of interest with regard to the horizontal thrust of sand. As will be seen below, the nature of those conclusions was such that the renewal of the experiments seemed inexpedient. An important paper by Mr [afterwards Sir] Benjamin Baker, M. Inst. C.E., on the lateral pressure of earthwork, was read before the Institution of Civil Engineers in 1878, and excited a discussion of much interest. That paper, which has only recently been brought under the Author's notice, afforded the immediate inducement for bringing forward his results.